Compiler Option and String Handling

       1.      What compiler option would you use for dynamic linking? DYNAM.      2.      What is SSRANGE, NOSSRANGE ? These are compiler o...

     1.     What compiler option would you use for dynamic linking?

DYNAM.

     2.     What is SSRANGE, NOSSRANGE ?

These are compiler options wrt subscript out of range checking. NOSSRANGE is the default and if chosen, no run time error will be flagged if your index or subscript goes out of the permissible range.

     3.     What care has to be taken to force program to execute above 16-MB line?

Make sure that link option is AMODE=31 and RMODE = ANY.

Compile option should never have SIZE(MAX).

BUFSIZE can be 2K, efficient enough.

     4.     What are AMODE and RMODE? What is AMODE(24), AMODE(31), RMODE(24) and RMODE(ANY)? What do 24 or 31 mean to it? ( applicable to only MVS/ESA Enterprise Server).

Addressing Mode/Access Mode

AMODE(24) indicates 24-bit (three-byte) addressing - memory below the line.

AMODE(31) indicates 31-bit addressing - memory above and below the line.

AMODE=ANY indicates the program may use either of the addressing technique.

Run Mode/Residency Mode

RMODE(24) indicates that the program must be loaded into memory below the line. Resides in virtual storage below 16-MB line. Use this for 31 bit programs that call 24 bit programs. (OS/VS Cobol programs use 24 bit addresses only).

RMODE(31) indicates that the program can be loaded either below or above the line.

RMODE=ANY indicates that the program can be run in either 24 bit (below)or 31 bit memory (above). 

These are compile/link edit options.

AMODE  - Addressing mode. RMODE - Residency mode.

AMODE(24) - 24 bit addressing.

AMODE(31) - 31 bit addressing.

AMODE(ANY) - Either 24 bit or 31 bit addressing depending on RMODE.

RMODE(24) - Resides in virtual storage below 16-MB line. Use this for 31 bit programs that call 24 bit programs. (OS/VS Cobol programs use 24 bit addresses only).

RMODE(ANY) - Can reside above or below 16 MB line.

Character Handling

     5.     What is the Purpose of POINTER Phrase in STRING command?

The Purpose of POINTER phrase is to specify the leftmost position within receiving field where the first transferred character will be stored

     6.     How will you move the part of character field to other character field?

By Reference modification

e.g.,.

To move the first 4 Chars of a variable ABC to XYZ:

MOVE ABC (1:4) TO XYZ